čt 29. 8. 2024 v 23:54 odesílatel Jim Jones <jim.jo...@uni-muenster.de> napsal:
> > > On 29.08.24 20:50, Pavel Stehule wrote: > > > > I know, but theoretically, there can be some benefit for CANONICAL if > > pg supports bytea there. Lot of databases still use non utf8 encoding. > > > > It is a more theoretical question - if pg supports different types > > there in future (because SQL/XML or Oracle), then CANONICAL can be > > used without limit, > I like the idea of extending the feature to support bytea. I can > definitely take a look at it, but perhaps in another patch? This change > would most likely involve transformXmlSerialize in parse_expr.c, and I'm > not sure of the impact in other usages of XMLSERIALIZE. > > or CANONICAL can be used just for text? And you are sure, so you can > > compare text X text, instead xml X xml? > Yes, currently it only supports varchar or text - and their cousins. The > idea is to format the xml and serialize it as text in a way that they > can compared based on their content, independently of how they were > written, e.g '<foo a="1" b="2"/>' is equal to '<foo b="2" a="1"/>'. > > > > > +SELECT xmlserialize(CONTENT doc AS text CANONICAL) = > > xmlserialize(CONTENT doc AS text CANONICAL WITH COMMENTS) FROM > > xmltest_serialize; > > + ?column? > > +---------- > > + t > > + t > > +(2 rows) > > > > Maybe I am a little bit confused by these regress tests, because at > > the end it is not too useful - you compare two identical XML, and WITH > > COMMENTS and WITHOUT COMMENTS is tested elsewhere. I tried to search > > for a sense of this test. Better to use really different documents > > (columns) instead. > > Yeah, I can see that it's confusing. In this example I actually just > wanted to test that the default option of CANONICAL is CANONICAL WITH > COMMENTS, even if you don't mention it. In the docs I mentioned it like > this: > > "The optional parameters WITH COMMENTS (which is the default) or WITH NO > COMMENTS, respectively, keep or remove XML comments from the given > document." > > Perhaps I should rephrase it? Or maybe a comment in the regression tests > would suffice? > comment will be enough > > Thanks a lot for the input! > > -- > Jim > >
